The invention generally relates to blood collection and processing systems and methods.
Systems composed of multiple, interconnected plastic bags have met widespread use and acceptance in the collection, processing and storage of blood components. Using these systems, whole blood is collected and separated into its clinical components (typically red blood cells, platelets, and plasma). The components are individually stored and used to treat a multiplicity of specific conditions and diseased states.
Before storing blood components for later transfusion, it is believed to be desirable to minimize the presence of impurities or other materials that may cause undesired side effects in the recipient. For example, because of possible reactions, it is generally considered desirable to remove substantially all the leukocytes from blood components before storage, or at least before transfusion.
Filtration is conventionally used to accomplish leuko-reduction. Systems and methods for reducing the number of leukocytes by filtration in multiple blood bag configurations are described, e.g., in Stewart U.S. Pat. No. 4,997,577, Stewart et al. U.S. Pat. No. 5,128,048, Johnson et al. U.S. Pat. No. 5,180,504, and Bellotti et. al. U.S. Pat. No. 5,527,472.
The invention provides a blood collection system comprising a container for holding blood and a filter communicating with the container. The filter includes first and second flexible sheets comprising a meltable material and a depth filter medium comprising a meltable material. A peripheral seal joins the sheets directly to the filter medium to encapsulate the filter medium between the first and second sheets. The seal comprises a commingled melted matrix comprising material of the sheets and material of the filter medium.
In a preferred embodiment, the filter medium removes leukocytes from blood.
Other features and advantages of the invention will become apparent upon review of the following description, drawings, and appended claims.